I found this ==>
http://sales.goldmine-elec.com/prodinfo.asp?prodid=4520
I have very little info on them
, but am going to try to wire some in parallel and see what happens. At 5 for $1, the price is right...so I got a few dollar's worth (along with parts for my adjustable 2 stage booster idea). They claim 3v DC, but im not sure the capacity. They say "We charged one up and it powered a flashing LED for about an hour before needing to be recharged" and "Has rating of .6 Farad". I'm not sure, but I think most FLEDs draw like 20 mA, so, each one might be like 3v, 20 mAh. I'm not sure how the Farad rating will work, I'm new to electronics. Even if i can only match stock capaciy, the voltage is still doubled.